The result of rename(x,dim,names) is x reordered such that dimnames(x)[[dim]]
is equal to the concatenation of those elements of names that are in
dimnames(x)[[dim]] and the remaining elements of dimnames(x)[[dim]].

The result of rename(x,dim,indices) is x reordered along dim according to
indices.

The result of rename(x,dim,FUN) is x reordered along dim according to
order(apply(x,dim,FUN)).